Stapling machine



Feb. 13, 1934. H. B. WALTER 1,946,773

STAPLING MACHINE Original Filed July 31. 1929 3 Sheets-Sheet 1 Feb. 13, 1934. H, B, WALTER V1,946,773

STAPLING MACHINE Original Filed July 3l. 1929 5 She'ets-Sheet 2 Feb. 13, 1934. H. B. WALTER 1,946,773

STAPLING MACHINE Original Filed July 31. 1929 3v Sheets-Sheet 5 Cal Patented Feb. 13, 1934 UNITED STATESl PATENT OFFIACE STAPLING MACHINE Application .my 31, 1929, semi No. 382,337

Renewed July 2s. 1933 6 Claims. (Cl. 1'-11) The present invention relates to stapling machines and more especially to stapling machines of the type adapted for stapling in place the ends or closures of recessed end boxes, one object of the invention being to generally improve upon the construction and operation of stapling machines of this type. Another object of the invention is the provision of an improved mechanism for controlling the movement of a movable clenching block from its inoperative to its operative position. Another object of the vinvention is toprovide an improved means for controlling the operation of the driving clutch for the staple driving mechanism. Still another object is to so mount all of the operating parts on the frame of the machine that they may be readily moved to a-position in which they are easily accessible for inspection and repair. A further object of the invention is to provide a stapling machine of this type which is adapted to drive staples in the heads of recessed end boxes which staples are diagonally disposed with relation to the end edges of the box.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. 1 is a side elevation of the improved stapling machine;

Fig. 2 is a front elevation on an enlarged scale, and shown partly in section along line 2-2 of Fig. l;

' Fig. 3 is a fragmentary front elevation, similar to Fig. 2, but showing the clenching block in lowered oroperative position;

Fig. 4 is a sectional plan view taken substantially along line 4 4 of Fig. 2;

Fig. 5 is a detail plan view of a guide bar for maintaining the box in proper position relatively to the stapling mechanism;

Fig. 6 is a detail view of the clutch for conr trolling the stapling mechanism;

Fig. 7 is a detail view o! the guide block for the clenching block illustrating the means foi' maintaining a snug engagement between' the parts; and

Fig. 8 is a fragmentary detail view of a recessed-end box having the closure thereof secured by diagonally disposed staples.

Similar reference numerals throughout the several views indicate the 'same parts.

The present embodiment of the invention provides an apparatus of the class described composed of comparatively simple parts, sturdy in construction and capable of ready assembly to form a mechanism which is easy to adjust and operate. The present invention is particularly there is shown in Fig. 1 a stapling machine embodying the present invention which includes a base 10, a support orhead frame 11 carried thereby and preferably inclined at an angle thereto, and the stapling mechanism. designated generally at 12, supported in the head frame.

The base may be of a more or less usual construction and comprises a base plate 13 on which a standard or column 14 is rigidly secured. Surrounding the column 14 is a telescoping casing 15 slidably guided thereon for the purpose of supporting the stapling mechanism at different elevations to accommodate different sizes of boxes.

In order to raise and lower the casing 15 of the base 10 there is provided an adjusting screw 16 threaded into a suitable portion 17 on the column 14. A collar 18 is secured on the screw 16 and bears against a plate 19 which forms the upper end of the casing 15 to thus support the casing with relation to the screw 16. Suitable means are provided, and will be presently described, for giving rotation to the screw 16. fA clamping screw 20, having a suitable handle 21, is threaded through the casing 15 and bears against the side of column 14 to rigidly hold the parts 14 and 15 in any adjusted position.

While the head frame 11 may be supported on the base in various ways, in the present instance, this frame is preferably supported at approximately a angle to the base. Obviously the particular inclination of the frame 11 may be varied but, for reasons which will later be more fully pointed out. this angle should preferably be somewhere between 25 and 45. In order to provide for mounting the frame 1l at an inclination to the base there is employed, in the present instance, an angle casting 22 having a horizontally disposed portion 23 secured by suitable means such as bolts or rivets to the plate 19 oi' the outer casing 15. The inclined portion 24 of the casting 22 is of a suitable length to engage beneath substantially the entire lower end of the frame 11 which is rigidly secured thereto, as by means of bolts 25.

The frame 11 may be made in any desired way to support the stapling head 12 but, in the pres- The mechanism for rotating screw 16 will nowA be described. The angle casting 22 is provided with bearing portions 26 and 27 which project into the lower part of the frame 11 which is suitably slotted for this purpose. The upper end of screw 16 is provided with a journal fitted into the bearing portion 26 and, at its upper end, the screw 16 has keyed thereto a bevelled pinion 28 which meshes with a similar bevelled pinion 29 keyed to a shaft journalled in bearing portion 27 and on the other end of which shaft there is secured a hand wheel 30 by which the parts may be operated to raise or lower the casing 15 with relation to the base.

'I'he stapling assembly 12 is suitably mounted within the frame l1 for movement therein from operative to inoperative position to permit ready access thereto for purposes lof inspection and repair. In the present instance, the stapling assembly 12 is pivotally mounted adjacent the upper end of the frame 1l and for this purpose there is provided a suitable frame member. prei'- erably in the form of a casting, having a central portion 31 provided with trunnions 32 and 33 at each end thereof journalled in suitable bearings on frame 11. The trunnion 32 has a collar 34 keyed thereto so as to prevent endwise movement of the member 31 relatively to the frame. The trunnion 33 is threaded at its end and provided with a wing nut 35 by means of which the stapling frame may be held in proper operative position within the frame 11.

The staple driving mechanism is enclosed within a casing 36 secured at the lower end of a suitable vertical casing 37 formed integrally with the frame portion 31 and housing a vertical shaft 38, see Fig. 4, which forms a part of the driving gear for the stapling mechanism. The lower side of casing 36 is closed by a suitable hinge plate or door 40 adapted to be swung away from casing 36 when it is desired to replace any of the parts of the stapling machine proper. The door 40 is suitably secured in closed position by means Vof a bar 4l pivoted at 42 on one side of the casing 36 and at its other end provided with a notch adapted to engage about a machine screw 43 whereby the bar may be held in fixed position to maintain the door 40 closed.

The material from which the staples arel formed is preferably in the shape of a continuous strip of metal wound upon a reel 44 rotatably mounted on a spindle 45 which is secured on a swinging arm 46. The arm 46 is suitably mounted on a lug 47 on the frame 11 by means of a machine screw 50 which may be tightened to hold the arm 46 in various angularly adjusted positions. Suitable braking means such as a leaf spring 48 is provided upon the arm 46 so that its end bears against one flange of the reel 44 to act as a brake or tensioning means for the reel.

The vertical shaft 38 in the casing 37, see Figs. 3 and 4, bears suitable gearing at its lower end connecting it to the stapling mechanism and has at its upper end a flywheel 51 freely rotatable thereon. The ywheel 51 bears, preferably on its upper surface, a gear ring 52 meshing with a pinion 53 on the shaft of a motor 54 supported on frame l1 in a manner which will be later described.

Means are provided for disengageably connecting flywheel 5l to the shaft 38 and for this 1,945,775" Y A ent instance, this frame is U-shaped and has its purpose there is secured or formed on the ywheel 51 a clutch element 55 disposed coaxially with the shaft 38. The clutch element 55 has one or more notches in the face thereof provided with shoulders 56 adapted to be engaged by the end of a pin 57 longitudinally slidable within the complementary clutch element which is keyed or otherwise suitably secured to the shaft 38. For the purpose of sliding the pin 57 longitudinally to engage or disengage the clutch elements it is provided with a laterally extending lug 58 bearing on a compression spring 59 which is supported in a recess in the clutch element 66. The compression spring 59 acts to move the pin 57 in the direction of the notched face on clutch element 55. Thus when the spring 59 forces the pin 57 outwardly it will be engaged by one of the shoulders 56 on the clutch element 55 and will thus start the rotation of shaft 38 to set the stapling mechanism into operation.

The pin 57 will be normally held in inoperative relation by means of a swingably mounted finger member 61 pivoted to the frame porti n 37 at 62. The finger member 61 at its free end and on that side adjacent the clutch has a bevelled edge 64 which is adapted to engage with a suitable cam surface 65 on pin 57 to withdraw the end of the pin 57 from engagement with the shoulder 56. The finger member 61 may be returned to its disengaging position within the notch 63 at any time during rotation of the clutch and when returned to such position it will engage the cam surface 65 on the pin 57 on the next revolution of the clutch and withdraw the pin 57 longitudinally from in front of shoulder 56.

The finger member 6l is provided at its free end with an outwardly projecting member carrying a pin 71 to which is secured the end of a tension spring 72 which has its other end flxed to a bracket 73 bolted or otherwise secured to an arm 74 projecting from the frame portion 3l. This spring 72 will tend to hold the finger member 61 in position to maintain the pin 57 in its inoperative position in which clutch elements 55 and 6D will be disengaged. In this condition of the clutch elements the motor may be driven to rotate the flywheel 5l and clutch element 55 which will turn idly on the end of shaft 38.

The staple driving mechanism enclosed in casing 36 is of generally conventional form and need not be described in detail as it forms, per se, no part of the present invention. This mechanism is generally shown in United States Patents granted to Edward Craig, No. 1,253,354, issued January 15, 1918, and No. 1,280,410, issued October l, 1918, to which patents reference is made herein for a more detailed disclosure of the staple driving mechanism. For the present purposes it will suffice to state that the metal strip stored on the reel 44 is fed through the stapling mechanism Where it is cut into suitable lengths and driven into the material in the form of staples.

In order to properly clench the ends of the staples which are driven by the stapling mechanism there is provided a clenching block 76 having a suitable face plate 77 adapted to properly turn and clench the ends of the staples.

It is very desirable in machines of the present type to provide means for raising or lowering the clenching block as such an expedient allows the work, such as the flange of a recessed end box, to be brought into operative stapling position merely by moving the box toward the staple driving mechanism entirely in a horizontal direction. This arrangement is particularly advantageous for use with the rolling deck disclosed in my prior Patent No. 1,253,754, issued January 15, 1918. In the preferredform of the invention the clenching block 76 is slidably mounted in a. recess in a guide block 78 secured to the arm 74 of the frame 31. Since it is desirable 'to provide for adjusting the angle of the clenching block with relation to the face of the stapling mechanism the guide block 78 is preferably pivotally mounted on the arm 74 by means of a bolt 79 threaded into the arm 74 and provided on its outer end with a jam nut 80. Thus by loosening bolt 74 the guide block 78 may be tilted so as to cause the clenching block to approach or recede from the face of the stapling mechanism.

In order to securely maintain the guide block 78 in any xed position there is preferably provided a pair of set screws 81, 81 threaded through a lug or bracket 82 on arm 74 and bearing at their ends against the side of guide block 78, substantially as shown in Fig. 2.

An additional' guiding means for the clenching block 76 is preferably provided and in the pres- Aent instance this guiding means is in the form of acrosshead member 83 embracing three sides of the guide block 78 and secured to the clenching block 76 by means of bolt 84.

The mechanism for raising and lowering the clenching block 76 will now be described. This mechanism preferably comprises a linkage system adapted to be operated by the foot of the operator and for this purpose Ythere is provided a treadle 85 suitably pivoted on the base 10 and connected by means of an extensible link 86 to the end of a lever 87 which is pivoted in a suitable manner on the angle casting 22. An additional link 90 connects lever 87 with one end of a bell crank lever 91 pivoted at 92 upon the frame portion 37 of the stapling head. The opposite end of bell crank lever 91 is connected to the end of a toggle lever 93 by meansof a link 94. The toggle lever 93 is pivotally mounted on a machine screw 95 threaded into the head of bolt 79 which supports the guide block 78. .l toggle link 96 is pivoted at its upper end at 97 to the lower end of toggle lever 93 and the lower end of link 96 is pivoted on the previously mentioned bolt 84 which secures the crosshead 83 to the clenching block 76. It wilLihus be seen, by referring to Figs. 2 and 3, that when the upper end of toggle lever 93 is swung outwardly or to the right, as viewed in these figures, the clenching block will be moved to its inoperative position, as clearly shown in Fig. 2. When the upper end of toggle lever 93 is moved inwardly or to the left, as viewed in these figures, the clenching block will be moved to a lowered or operative position as shown in Fig. 3.

It will be further noted that when the operating links and levers are in the position shown in Fig. 3 the pivot point 97 between the lever 93 `and link 96 will have moved beyond a vertical line passing between pivot points 84 and 95. In this position of the parts they are temporarily locked, thus making it impossible for the clenching block 76 to become displaced upwardly during the stapling operation. The link system can move no further in the direction of lowering the clenching block by reason of the fact that the i'oot treadle will at this time be in an extreme depressed position. g

Mechanism. is provided for actuating the clutch operating device substantially coincident with the movement of the clenching block to its operative position and for this purpose the link 94 has secured thereto an upstanding bracket 100 to which there is pivotally secured a link 101 having a slot 102 in which is disposed the end of pin 71 on the clutch finger 61. By reference to Figs 2 and 3 it-will be seen that during the major portion of the movement'of the link 101 to the left, as viewed in Fig. 2, the slotted portion of the link 101 will move along the pin 71 without affecting the clutch operating parts but when the link 101 reaches nearly the end of its movement the end of slot 102 will engage with the pin 71 to move it slightly to the left suflicient to withdraw the finger member 61 from` engagement with the pin 57 to thus allow its spring to force it upwardly into engagement with one o f the shoulders 56 on the clutch element 55 and thus set the stapling 4mechanism into operation.

The extensible link 86 for the treadle 85 comprises two sections 103 and 104, provided with suitable clamping members 105 and 106 by which the links may be held -in any extended position. A spring 107 is arranged to normally hold` the treadle 85 in its inoperative position. This`spring is preferably secured to the clamping member 106 at `one end and, at its other end, the spring is secured at a suitable point on the casing 15 of the base. The upward movement of the treadle 85 may be conveniently limited as by. means of a 'yoke 108 into which a set screw 109 is threaded, the lower end of the set screw 109 bearing against the treadle.

As previously described, the stapling head is mounted in the head frame -11 for movement from operative to inoperative position therein. It is, accordingly, desirable to provide means for limiting the return movement of the staplingmechanism to its operative position. This means, in the present instance, comprises a pair of lugs 110 and 111 respectively secured on frames 31 and 11', as shown in Figs. 1 and 4. In order to adjust the position at which the stapling frame will stop there is preferably provided a set screw 112 threaded into lug 111 and bearing at its end against lug 110.

The mounting of motor 54 will now be described. It will be observed that since the motor 54 is mounted on a fixed part of the frame 11 it will be necessary to provide for the separation of the motor pinion 53 from the gear ring 52 when it is desired to tip the stapling mechanism to its inoperative position for inspection and repair. This is taken care of by pro-- viding the base 113 of the motor with a bracket 114 which` is pivotally mounted at 115 on the frame 11. For adjusting the position of the motor 54 there is provided a screw 116 having its end pivotally connected at 117 to the base 113 and having its threaded end provided with I` thumb nuts 118, 118 which engage on either side of a lug 119 projecting from frame 11.

A suitable guard member 120 for the gears 52 and 53 is secured on the motor frame to swing therewith. It will thus be seen that when it is desired to swing the stapling mechanism to inoperative position it is first necessary to swing motor 54vbackward suillciently to permit the gear ring 52 to clear the pinion 53. The motor will be held in its inoperative position by the nuts 118 on screw 116 until itis desired to return the motor to its operative position.

In order to facilitate the positioning and movement of the box to be stapled there is preferably mounted on the door 38 of casing 36 a roller 121. This roller projects outwardly a slight amount and spaces the box properly with relation to the stapling mechanism when the box ,is moved thereagainst.

Means are provided for maintaining at all time a snug contact between the crosshead 83 and the guide block 78. For this purpose one leg of the guide block 78 is provided with a slit 122 and is threaded for the reception of a suitable stud 123. By turning the stud 123 to move it further into the guide block 78 a spreading of the parts on either side of the slit will be effected. The stud 123 will be held in any adjusted position by means of a jam nut 124.

Guiding means is preferably provided for insuring the proper positioning of the box or other article to be stapled. In the present instance this guiding means is in the form of a bar 125, preferably of wood, which is suitably supported by means of bolts passing through lugs 126 and 127 formed respectively on the frame 11 and angle member 22. The bar 125 is provided with a suitable curved recess 128 in substantially ver,- tical alignment with the clenching block.

This recess permits greater facility in turning the box to present successive sides in operative relation with the stapling mechanism. In other words the recess 128 receives the corners of the box which is being stapled. Thus the box may be stapled along one side and then turned and stapled along the next side without lifting the clenching block orl stoppingthe staple driving mechanism.

In order to prevent any overrun of the clutch element when it has been released from the clutch element 55 there is provided a brake member 133 having a brake surface bearing against the lower periphery of clutch element 60 and tensioned thereagainst by means of a spring 134 surrounding a stud 135 which passes through the central portion of the brake member and is threaded into the frame 37. A nut 136, threaded onto the stud 135 is provided for changing the compression of the spring 134.

The operation of the device will now be described. Assuming that it is desired to secure in place the end closures of a recessed end box, the operator will preferably employ the rolling deck and form such as shown in my prior Patent No. 1,253,754. This mechanism is diagrammatically shown herein by dotted lines on Fig. 1, the recessed end box being shown at 130, the rolling deck at 131 and the table or other support at 132. If the recessed end is to be secured in place before any material is packed in the box a form substantially like that shown in my said patent will be placed upon the rolling deck to support the recessed end or head in the proper position. It will be seen that, by reason of the rolling deck being supported on the table or support 132, theoperator will be able to turn the box or move it horizontally in a straight line in any direction. With the box properly placed upon the'deck 131 the operator will be ready to begin the stapling operation.

The operator, after starting the motor 54, will take a position on the left of the machine as viewed in Fig. 1, or in front of the machine as shown in Fig. 2. He will first move the box laterally toward the staple driving mechanism until it engages the roller 121 and the guide bar 125, see Fig. 2. With the box in this position and preferably with the stapling mechanism adjacent a corner of the box, the operator will depress the treadle 85 to lower the clenching block 76 and throw in the clutch to start the staple driving mechanism. As the staples are driven into the flanges of the box the operator will move the box to properly space the staples, and, upon completion of the stapling of one side of the box, the operator will turn the entire box to present the succeeding sides to the stapling mechanism. As above described, the recess 128 facilitates turning the box by guiding the corner thereof during the process of changing from one side to another.

After the box has been completely stapled on .all sides the operator will release the treadle 85 to allow its spring 107 to move it upwardly whereby the clenching block will be returned to its inoperative position. When this movement takes place the link 101 will be moved from en- L`gagement with the pin 71 whereby the clutch finger 61 will be drawn by spr/ing 72 to the right, as viewed in Figs. 3 and 4. With the finger 61 in the notch 63 the bevelled end 64 of the finger 61 will be in position to engage the cam surface 65 on the pin 57 as soon as the rotation of clutch y element 60 carries the pin 57 past said finger.

i( The engagement of the bevelled end of finger 61 105 @with the cam surface on the pin 57 causes the immediate withdrawal of the end of pin 57 from engagement with the shoulder 56 on the clutch element 55. As soon as the clutch element 60 has been disengaged from clutch element 55 by the withdrawal of pin 57 the clutch element 60 will be stopped from further rotation by the brake 133.

When the operator desires to inspect, adjust or repair the staple driving mechanism this will be done by first swinging the motor support 113 to the right, as shown in Fig. 1, until themotor pinion 53 and guard 120 are clear of the gear ring 52. The operator will then release clamps 105 and 106 to permit the extensible link 86 to be readily lengthened after which the wing nut 35 is partly unscrewed from frictional engagement with the head frame 1l. The stapling mechanism proper, supported on the trunnions 32 and 33, may be swung in a clockwise direction, as viewed in Fig. 3, to a position in which the casing 36 which encloses the staple driving mechanism is disposed substantially vertical.

After the necessary adjustments or repair of the stapling mechanism the operator will again return the stapling mechanism to its upright position. the proper position being determined by stop lugs 110 and 111, after which the wing nut 35 will be tightened. The clamps 105 and 106 on the extensible link 86 will again be secured in proper position, the motor 54 will be swung down into place and the machine is again ready for further operation. It will be obvious that the device of the present invention is not limited in its use to stapling the flanges of recessed end boxes but may also be employed in the stapling of any upwardly presented meeting edges.

It will be further apparent that the present embodiment of the invention provides a mechanism of a compact and sturdy form, comparatively simple in its operation and adjustment of parts, the device being particularly advantageous for the insertion of diagonally placed staples in the flanged edges of recessed end boxes. The insertion of diagonally placed staples provides a 15 'staples in this manner.

stiffer iiange or edge portion than is the case when the staples are placed parallel to the edge and, in addition to this, when the staples are placed diagonally they will nearly always extend across the grain of the material and not with the grain. The only possible exception would be where the box blanks are not cut symmetrically with the grain of the material or where other than rectangularly shaped blanks are used.

If for any reason it is desired to insert staples in the flanges of a box which are parallel to the edges of the flanges the present device may be readily converted to adapt it to drive This will be done by removing the angle member 22 and by securing the head frame 11 directly to the horizontal portion 19 on the casing l5 of the base. By the same token machines of this type which may have previously been adapted for driving horizontally disposed staples may be readily converted to adapt them for driving diagonally disposed staples. When the machine is employed for driving horizontally disposed staples the shafts for gearings 28 and 29 and hand wheel 30 will be suitably journalled directly upon the frame 11.

While the present description sets forth a preferred embodiment of the invention, numerous changes may be made in the construction without departing from the spirit of the invention, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not'restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

I claim:

1. In a stapling machine, the combination of a frame, a staple driving mechanism thereon, a movable clenching block supported on said frame and adapted to be moved from operative to inoperative position relatively to said staple driving mechanism, a linkage system adapted to be controlled by an operator for moving said clenching block, control means for said staple driving mechanism, means operably connected to said linkage system for actuating said control means just prior to the movement of the clenching block to its final operative position, said linkage system including means for temporarily lockingjthe clenching block in its operative position during the operationk of the stable driving mechanism.

2. In a stapling machine, the combination with a frame, a staple driving mechanism supported thereon, a clenching block for said staple driving mechanism adapted for movement from operative ito inoperative position relatively to said staple driving mechanism, a guide block for said clenching block, said guide block being supported on said frame and formed with a slotted opening snugly engaging said clenching block and in which said clenching block is adapted to slide from its operative to its inoperative position, additional means for guiding said clenching block comprising a crosshead member'secured to said clenching block and embracing said guide block on at least two sides thereof, and means associated with said guide block for insuring a snug engagement of said crosshead member on said guide block in the position,

driving mechanism adapted for movement from operative to inoperative position relatively to said staple driving mechanism, a guide block for said clenching block, said guide block being supported on said frame and formed with a slotted opening snugly engaging said clenching block and in which said clenching block is adapted to slide from its operative to its inoperative additional means for guiding said clenching block comprising a crosshead member secured to said clenching block and embracing said guide block on at least two sides thereof and means associated with said guide block for insuring a snug engagement'of said crosshead member on said guide block in the operative position of said clenching block, said means comprising a split portion in the end of said guide block having threaded therein a tapered machine screW-adapted to spread the parts when said screw is turned in a direction to force it into said guide block.

4. In a stapling machine, the combination with a stapling mechanism and a frame supporting said mechanism, a support for said frame, trunnions on said frame for rotatably mounting said frame on said support, cooperative stop lugs on said frame and said support for limiting the swinging of said frame in one direction and a set screw on one of said stop lugs for varying the angle at which said frame will be stopped.

5. In a stapling machine, the combination of a base member for the stapling machine, a stapling mechanism, a head frame for supporti-ng said stapling mechanism, said head frame being of substantially rectangular coniiguration and said stapling mechanism being supported in substantially right angular relation to said head frame, an angle member having -tWo supporting surfaces disposed at an acute angle relatively to each other, said angle member having one of its surfaces secured upon a horizontal surface on the base member and having the other of said surfaces secured to and supporting /said head frame whereby said head frame and stapling mechanism are inclined relatively to said base and whereby staples driven by the stapling mechanism will be diagonally disposed relatively to a generally horizontal line of staples inserted by the stapling mechanism.

6. In a stapling machine of the type comprising a base, a head frame adapted to be supported thereon, a stapling mechanism supported by said head frame, said head frame being of substantially rectangular configuration, and said stapling mechanism being supported in substantially right angular relation to said head frame whereby, when said head frame is supported directly upon said base, the staples driven by said stapling mechanism will be disposed in substantially parallel relation to the edge of an article to be stapled, an angle member for cooperation with said base and head frame, said angle member having at least two faces thereof disposed at an acute angle to each other, said angle member adapted to be interposed between said base and said head frame whereby said head frame will be supported at an angle to said base and whereby the staples driven by the stapling mechanism will be disposed at an angle to a generally horizontal line of staples inserted by the stapling mechanism.

` HARRISON B. WALTER. 

